Recently, a portable communication unit, such as a mobile telephone, has function of a data terminal for furnishing various informations as well as that of a telephonic communication though a voice, and is spread throughout the world during the past few years. The portable communication unit affords full facilities for transmitting and receiving information because of its excellent portability, which is an extremely important factor of this instrument. In the portable communication unit, since it is indispensable to have function of communication through the voice, a sound-sensing device, such as a microphone, should be situated close by the mouth, and a sound-generating device, such as a speaker, should be situated close by the ear. Accordingly, the length of an external shape of the portable communication unit must be nearly the same as an interval between the mouth and the ear, so that it becomes considerably large.
Form this point of view, a fording portable communication unit shown in FIGS. 1A, 1B has been devised heretofore. FIGS. 1A, 1B are perspective views for showing an external shape of a conventional folding portable communication unit. FIG. 1A shows a state that cabinets of the folding portable communication unit are opened, and FIG. 1B shows a state that the cabinets thereof are closed. As shown in FIGS. 1A, 1B, the conventional folding potable communication unit is composed of an upper cabinet 100, a lower cabinet 102, and a hinge 104 for so supporting the upper and lower cabinets 100, 102 that they are rotational around the hinge 104 in broad outline.
The upper cabinet 100 is provided with an antenna 106 for transmitting and receiving electric waves, a speaker 108 for converting aural information received by the antenna 106 into a voice and indicating it to a user, and a liquid crystal display (LCD, hereinafter) 110 for displaying various informations. The lower cabinet 102 is provided with a key unit 112 for inputting a data to be transmitted from the user in accordance with his operation, and a microphone 114 for converting a voice of the user into an audio signal. In case that the user uses the folding portable communication unit, he opens the upper and lower cabinets 100, 102 as shown in FIG. 1A, and operates the key unit 112 or speaks over the folding portable communication unit. When he does not use the folding portable communication unit and brings it with him, the upper and lower cabinets 100, 102 are closed as shown in FIG. 1B.
However, in the conventional folding portable communication unit, the single LCD 110 for displaying various informations and the single key unit 112 for inputting the data to be transmitted from the user are respectively provided, and the LCD 110 and the key unit 112 are exposed only when the upper and lower cabinets 100, 102 are opened. Accordingly, when the upper and lower cabinets 100, 102 are closed, the user can neither watch the LCD 110 nor operate the key unit 112.
In recent years, the portable communication unit has come to be used not only as means for transmitting and receiving voice information but also as a data terminal for furnishing the various data, and function as the data terminal is given much weight. Accordingly, it is expected in general that the portable communication unit in future will be required to be compact, light weight, easy to see the LCD and highly operable. However, if the portable communication unit becomes too small by regarding compactness and lightness as important excessively, the surface area of the whole portable communication unit is reduced, and the man machine interface, such as the LCD or the key unit, becomes too small, so that the portable communication unit becomes hard to operate. The aforementioned arguments hold in the case of the folding portable communication unit also.